1. Technical Field
The present invention relates to a method for the production of a piston for an internal combustion engine with at least one cooling channel and at least one reinforced piston ring groove and to a piston thus produced.
2. Related Art
Passenger car pistons, in particular pistons in diesel engines in passenger cars are exposed to high temperatures and pressures in use. For this reason, efficient cooling of the piston and reinforcement of points subject to high mechanical stresses is necessary. To this end, pistons for passenger car diesel engines are generally provided with cooling channels through which cooling oil and/or another coolant is passed to remove the heat from the piston.
A process for producing a piston with a cooling channel is known from DE 196 49 363 C2, for instance, in which a salt lost core is inserted in a cavity in a casting mould for a piston. The lost core is washed out after casting and solidification.
A process is further known whereby the piston is made with a reinforced or armoured ring carrier because of the high contact stress and wear stress in the first annular groove. In this regard, a process is known, for instance, whereby the ring carrier is integrated into the piston by means of what is known as the Alfin process. In this regard, the aluminium alloy piston is bonded with steel or cast iron during the casting process. To do this, the ring carrier must first be immersed in an aluminium-silicon melt (Al—Si melt). The ring carriers coated with the liquid melt are inserted into the casting tool and cast in.
DE 196 49 363 C2 discloses a process for forming an armoured annular groove in which the lost core is made from salt with an outer ring that is located at the position of the subsequent ring carrier in the piston. The outer ring is removed after the piston is cast and the space thus created is filled with a reinforcing material.
A significant share of the production costs of a piston for a diesel engine can be attributed to the production and/or manual insertion of an insert, such as the lost core. Furthermore, fluctuations in the positioning of the insert parts can lead to faults in production. Additionally, automated production of the pistons is not possible, or is only possible at high costs, because of the insert parts.